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Entanglement purification of Gaussian continuous variable quantum states

Lu-Ming Duan·G. Giedke·J. I. Cirac·P. Zoller
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Abstract

We describe an entanglement purification protocol to generate maximally entangled states with high efficiencies from two-mode squeezed states or from mixed Gaussian continuous entangled states. The protocol relies on a local quantum non-demolition measurement of the total excitation number of several continuous variable entangled pairs. We propose an optical scheme to do this kind of measurement using cavity enhanced cross--Kerr interactions.

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Lu-Ming Duan, G. Giedke, J. I. Cirac, P. Zoller. 2000-09-26. Entanglement purification of Gaussian continuous variable quantum states. https://doi.org/10.1103/physrevlett.84.4002

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